chain: json: use string to identify policy

* if we don't have hooknum we don't need to print the policy tag
* If we have hooknum, i have used the policy2str function for printing the policy with
"accept" string or "drop" string

Signed-off-by: Alvaro Neira Ayuso <alvaroneay@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

diff --git a/src/chain.c b/src/chain.c
index 35558299f9a22029735706290e4f53a9797fc62f..b59c5e09df53a27ca1785aad40b99312e26a9ef6 100644 (file)
--- a/src/chain.c
+++ b/src/chain.c
@@ -717,9 +717,24 @@ int nft_chain_parse(struct nft_chain *c, enum nft_chain_parse_type type,
 }
 EXPORT_SYMBOL(nft_chain_parse);
 
+static const char *policy2str(int policy)
+{
+       switch (policy) {
+       case NF_ACCEPT:
+               return "accept";
+       case NF_DROP:
+               return "drop";
+       default:
+               break;
+       }
+       return "unknown";
+}
+
 static int nft_chain_snprintf_json(char *buf, size_t size, struct nft_chain *c)
 {
-       return snprintf(buf, size,
+       int ret, len = size, offset = 0;
+
+       ret = snprintf(buf, size,
                "{ \"chain\": {"
                        "\"name\": \"%s\","
                        "\"handle\": %"PRIu64","
@@ -727,20 +742,32 @@ static int nft_chain_snprintf_json(char *buf, size_t size, struct nft_chain *c)
                        "\"packets\": %"PRIu64","
                        "\"version\": %d,"
                        "\"properties\": {"
-                               "\"type\" : \"%s\","
-                               "\"table\" : \"%s\","
-                               "\"prio\" : %d,"
-                               "\"use\" : %d,"
-                               "\"hooknum\" : \"%s\","
-                               "\"policy\" : %d,"
-                               "\"family\" : \"%s\""
+                               "\"family\": \"%s\","
+                               "\"table\": \"%s\","
+                               "\"use\": %d",
+                       c->name, c->handle, c->bytes, c->packets,
+                       NFT_CHAIN_JSON_VERSION, c->table,
+                       nft_family2str(c->family), c->use);
+               SNPRINTF_BUFFER_SIZE(ret, size, len, offset);
+
+       if (c->flags & (1 << NFT_CHAIN_ATTR_HOOKNUM)) {
+               ret =  snprintf(buf+offset, size,
+                               ",\"type\": \"%s\","
+                               "\"hooknum\": \"%s\","
+                               "\"prio\": %d,"
+                               "\"policy\": \"%s\"",
+                       c->type, hooknum2str_array[c->hooknum], c->prio,
+                       policy2str(c->policy));
+               SNPRINTF_BUFFER_SIZE(ret, size, len, offset);
+       }
+
+       ret = snprintf(buf+offset, size,
                        "}"
                "}"
-               "}",
-                       c->name, c->handle, c->bytes, c->packets,
-                       NFT_CHAIN_JSON_VERSION, c->type, c->table,
-                       c->prio, c->use, hooknum2str_array[c->hooknum],
-                       c->policy, nft_family2str(c->family));
+               "}");
+       SNPRINTF_BUFFER_SIZE(ret, size, len, offset);
+
+       return offset;
 }
 
 static int nft_chain_snprintf_xml(char *buf, size_t size, struct nft_chain *c)
@@ -780,19 +807,6 @@ static int nft_chain_snprintf_xml(char *buf, size_t size, struct nft_chain *c)
        return offset;
 }
 
-static const char *policy2str(int policy)
-{
-       switch (policy) {
-       case NF_ACCEPT:
-               return "accept";
-       case NF_DROP:
-               return "drop";
-       default:
-               break;
-       }
-       return "unknown";
-}
-
 static int nft_chain_snprintf_default(char *buf, size_t size,
                                      struct nft_chain *c)
 {